The origin of the triple-color photodetectors based on the ZnO/MgZnO films

A triple-color photodetector with MSM structure based on the ZnO/MgZnO films was fabricated. There are three response peaks in the response spectrum for the triple-color photodetector, which response peaks are located at around 290, 320 and 360 nm, respectively. A further study on responsivity for the triple-photodetector is carried out. The rising velocity of cubic MgZnO (111) response peak is faster than hexagonal MgZnO (002) response peak, the different internal gain between the different crystal orientation is the main reason for the different of the response peaks between the two phases. This experiment would have a great significance for multiple-colors photodetectors field.